Psychopathology - Bioloigcal explanation for OCD Flashcards
What does the biological approach to explaining OCD assume?
That OCD is caused by physiological factors such as brain biochemistry, neuroanatomy and genetics
What are the two biological explanations for OCD?
Genetic explanations
Neural explanations
What has the genetic evidence found about first degree relatives of people with OCD?
They have a greater vulnerability of developing the disorder
What did Nedstadt eat al 2000 find in his research on OCD?
That first degree relatives of OCD sufferers had a 12% chance of developing the disorder compared to a 3% risk in the general public - therefore the genetic explanation suggests that some people may inherit a genetic predisposition to developing an OCD
What gene has research found that may be responsible for OCD?
Candidate gene - involved in regulating the production of the neurotransmitter serotonin that is also implicated in OCD
What is one impaired gene that may correlate to OCD that is related to serotonin?
SERT gene - if this is impaired it leads to problems with the transport of the neurotransmitter serotonin. This ultimately leads to diminished levels of serotonin which correlates with cases of OCD
What did Osaki et al 2003 find?
A mutation of the SERT gene was found in 2 unrelated families where 6 out of 7 members had OCD
What is one impaired gene that is linked to OCD that involves dopamine?
Impaired COMT gene. This gene regulated the production of another neurotransmitter called dopamine. An impaired COMT gene leaves too much dopamine in the synapse, resulting in some of the compulsive behaviours seen in patients with OCD
What did Taylor 2013 find?
Identified up to 230 candidate genes that may contribute to OCD, which ultimately suggests that OCD is polygenic ie. OCD is caused by multiple genetic variants
What are 2 strengths of the genetic explanation for OCD?
Evidence from Nedstadt
Promotes psychology as a scientific discipline
What are 2 weaknesses of the genetic explanation for OCD?
Genes cant be the only factor in the development of OCD
Biologically reductionist - ignores other factors
what research support is there for the genetic explanation for OCD and what did they find ?
Nedstadt - review of twin studies found a concordance rate for OCD of 0.67 for MZ twins but only 0.3 for DZ twins. Hence, the closer the genetic relationship to a sufferer the greater the risk of developing OCD.
How does. the research for he genetic explanation of OCD demonstrate that genes can’t be the only factor in the development of OCD?
This is because if genes were the only explanation then the concordance rate for MZ twins would be 10% for OCD. But as this isn’t the case, there must also be environmental influences, like he impact of imitations/copying of role models such as parents that could explain some aspects of the behaviour.
how does the genetic explanation for OCD promote psychology as a scientific discipline ?
this is because genetics. can be studied objectively and reliably using DNA analysis and studying family history of OCD
Why is the genetic explanation for OCD considered bioloigcally reductionist?
Ignores factors other than genes that may affect the development of OCD such as the role of early trauma in childhood or some psychologists suggest that OCD may be learnt through classical conditioning and maintained through operant conditioning
